Highest temperature in NYC on July 5?

Platform comparison

Market context

The real-world event centres on the highest temperature recorded at LaGuardia Airport on 5 July 2026, with settlement depending on Wunderground data for that specific day. Current crowd-implied probability for a 74–75°F outcome sits at 0%, yet Polymarket’s frontrunner is actually 80–81°F at 38%, while Kalshi and Betfair often price the same event using decimal odds rather than implied probability, creating divergences in how traders interpret risk. Fee structures also vary sharply: Polymarket charges minimal fees with no KYC, whereas Kalshi mandates identity verification and Betfair applies higher commission rates, influencing liquidity depth on this narrow two-degree temperature band.

Historical precedents frame the current probability, as LaGuardia recently hit 102°F on a Thursday, breaking a daily high record, and recorded 94°F at midnight—surpassing the 93°F mark set in 2013[2][5]. July 2026 forecasts for LaGuardia show daily highs ranging from 81° to 99°F, suggesting the 80–81°F range is plausible but not dominant[6]. Traders should watch for NOAA Central Park announcements and the NWS forecast schedule, as thin volume of roughly $5,600 on this market amplifies price swings[4]. Recent coverage from Watchers News confirms the heat wave persists, with LaGuardia establishing its highest midnight temperature on record just before settlement[5][9].

Platform comparisons reveal where books diverge: Polymarket uses implied probability with no KYC, while Kalshi employs decimal odds and strict identity checks, and Betfair’s commission model may deter small traders. These structural differences mean the same 38% chance on Polymarket could translate to 2.63 decimal odds elsewhere, altering hedging strategies. Traders must monitor Wunderground’s daily update schedule, as settlement hinges on the highest temperature for all times on 5 July, and any delay in data release could shift odds across platforms. The heat wave’s persistence, confirmed by multiple sources, suggests temperatures will likely exceed 80°F, making the 0% implied probability for lower ranges a clear market mispricing.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Highest temperature in NYC on July 5? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. The live probability is the Polymarket mid; the comparison columns summarise each venue's fee structure, KYC, settlement currency and payment rails. Every CTA routes to Polymarket Alternative, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Settlement is the biggest difference between the four platforms: Polymarket on-chain in USDC (instant), Kalshi USD via CFTC (T+1), Betfair and Smarkets in local currency via bank withdrawal (T+1 to T+3). On-chain settlement clears in minutes — the fastest payout path of the four.

FAQ

What does Polymarket cost vs Kalshi?

Polymarket: 0% fees, only Polygon network costs (~$0.01/trade). Kalshi: up to 7% per trade plus spread. For high-frequency traders, Polymarket is dramatically cheaper.

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.

Which platform supports Klarna/SOFORT?

Directly: none. Polymarket accepts only USDC on Polygon. Polymarket Alternative offers a fiat on-ramp via Klarna or SOFORT (DE/AT/CH) and converts internally to USDC for the Polymarket order book. T+1 processing.